Arifureta Shokugyou de Sekai Saikyou Zero

The Liberators waged their own war long before any children from Earth arrived on the world of Tortus: a conflict with the gods themselves. Oscar Orcus was never one to seek conflict of that kind. As a magical craftsman, he leads a straightforward life. But when Miledi Reisen, a powerful magician, shows up in his life, he gets swept up in the events of history. Sparks that will ignite the entire world fly when the two of them meet!